AudioRecord: fix unwanted overrun when restarting

Apply the same fix to AudioRecord as this CL did for AudioTrack:
    > Change-Id: Id703f8dc092a6f07c905eee194054b4a978f979d

Details:
When restarting an AudioRecord from stopped state, it is necessary
to force refresh of mRemainingFrames by processAudioBuffer() as
the last read before stop() could be partial. No doing so will lead
into unnecessary sleep before filling the non contiguous part
of the buffer returned by obtainBuffer() when processAudioBuffer()
is executed for the first time after start().

Change-Id: I0ff04648e990e97bad5ea3db5be0c4151250d5e1